Oy Vey! where to start? If this bochur had two options, on the path he chooses to follow in his career, 1)all male touro, or 2)co-ed, of course he should choose
an all male environment, besides for his ruchnius, he would have an easier time
1)being more comfortable in an environment he’s used to,
2) no physical distractions. Isn’t that why he’s there? to learn!
If his career choice doesn’t come with that option,
I agree with “the wolf” that it really depends on the guy, background, maturity,
professionalism, etc.. some guys, considering their personality, it wuould be a
very bad idea. (not ending up in a kiddush Hashem as s/o put it.)